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            <div><h4 class="title">
                <a name="asio.reference.read_until.overload11"></a><a class="link" href="overload11.html"
                                                                      title="read_until (11 of 24 overloads)">read_until
                (11
                of 24 overloads)</a>
            </h4></div>
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    <p>
        Read data into a streambuf until it contains a specified delimiter.
    </p>
    <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
    <span class="keyword">typename</span> <a class="link" href="../SyncReadStream.html"
                                             title="Buffer-oriented synchronous read stream requirements">SyncReadStream</a><span
                class="special">,</span>
    <span class="keyword">typename</span> <span class="identifier">Allocator</span><span class="special">&gt;</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span
                class="identifier">read_until</span><span class="special">(</span>
    <span class="identifier">SyncReadStream</span> <span class="special">&amp;</span> <span
                class="identifier">s</span><span class="special">,</span>
    <span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">basic_streambuf</span><span class="special">&lt;</span> <span class="identifier">Allocator</span> <span
                class="special">&gt;</span> <span class="special">&amp;</span> <span class="identifier">b</span><span
                class="special">,</span>
    <span class="identifier">string_view</span> <span class="identifier">delim</span><span class="special">);</span>
</pre>
    <p>
        This function is used to read data into the specified streambuf until the
        streambuf's get area contains the specified delimiter. The call will block
        until one of the following conditions is true:
    </p>
    <div class="itemizedlist">
        <ul class="itemizedlist" type="disc">
            <li class="listitem">
                The get area of the streambuf contains the specified delimiter.
            </li>
            <li class="listitem">
                An error occurred.
            </li>
        </ul>
    </div>
    <p>
        This operation is implemented in terms of zero or more calls to the stream's
        read_some function. If the streambuf's get area already contains the delimiter,
        the function returns immediately.
    </p>
    <h6>
        <a name="asio.reference.read_until.overload11.h0"></a>
        <span><a name="asio.reference.read_until.overload11.parameters"></a></span><a class="link"
                                                                                      href="overload11.html#asio.reference.read_until.overload11.parameters">Parameters</a>
    </h6>
    <div class="variablelist">
        <p class="title"><b></b></p>
        <dl>
            <dt><span class="term">s</span></dt>
            <dd><p>
                The stream from which the data is to be read. The type must support
                the SyncReadStream concept.
            </p></dd>
            <dt><span class="term">b</span></dt>
            <dd><p>
                A streambuf object into which the data will be read.
            </p></dd>
            <dt><span class="term">delim</span></dt>
            <dd><p>
                The delimiter string.
            </p></dd>
        </dl>
    </div>
    <h6>
        <a name="asio.reference.read_until.overload11.h1"></a>
        <span><a name="asio.reference.read_until.overload11.return_value"></a></span><a class="link"
                                                                                        href="overload11.html#asio.reference.read_until.overload11.return_value">Return
        Value</a>
    </h6>
    <p>
        The number of bytes in the streambuf's get area up to and including the
        delimiter.
    </p>
    <h6>
        <a name="asio.reference.read_until.overload11.h2"></a>
        <span><a name="asio.reference.read_until.overload11.exceptions"></a></span><a class="link"
                                                                                      href="overload11.html#asio.reference.read_until.overload11.exceptions">Exceptions</a>
    </h6>
    <div class="variablelist">
        <p class="title"><b></b></p>
        <dl>
            <dt><span class="term">asio::system_error</span></dt>
            <dd><p>
                Thrown on failure.
            </p></dd>
        </dl>
    </div>
    <h6>
        <a name="asio.reference.read_until.overload11.h3"></a>
        <span><a name="asio.reference.read_until.overload11.remarks"></a></span><a class="link"
                                                                                   href="overload11.html#asio.reference.read_until.overload11.remarks">Remarks</a>
    </h6>
    <p>
        After a successful read_until operation, the streambuf may contain additional
        data beyond the delimiter. An application will typically leave that data
        in the streambuf for a subsequent read_until operation to examine.
    </p>
    <h6>
        <a name="asio.reference.read_until.overload11.h4"></a>
        <span><a name="asio.reference.read_until.overload11.example"></a></span><a class="link"
                                                                                   href="overload11.html#asio.reference.read_until.overload11.example">Example</a>
    </h6>
    <p>
        To read data into a streambuf until a newline is encountered:
    </p>
    <pre class="programlisting"><span class="identifier">asio</span><span class="special">::</span><span
            class="identifier">streambuf</span> <span class="identifier">b</span><span class="special">;</span>
<span class="identifier">asio</span><span class="special">::</span><span class="identifier">read_until</span><span
                class="special">(</span><span class="identifier">s</span><span class="special">,</span> <span
                class="identifier">b</span><span class="special">,</span> <span class="string">"\r\n"</span><span
                class="special">);</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">istream</span> <span
                class="identifier">is</span><span class="special">(&amp;</span><span class="identifier">b</span><span
                class="special">);</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span
                class="identifier">line</span><span class="special">;</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">getline</span><span
                class="special">(</span><span class="identifier">is</span><span class="special">,</span> <span
                class="identifier">line</span><span class="special">);</span>
</pre>
    <p>
        After the <code class="computeroutput"><span class="identifier">read_until</span></code> operation
        completes successfully, the buffer <code class="computeroutput"><span class="identifier">b</span></code>
        contains the delimiter:
    </p>
    <pre class="programlisting"><span class="special">{</span> <span class="char">'a'</span><span
            class="special">,</span> <span class="char">'b'</span><span class="special">,</span> <span class="special">...,</span> <span
            class="char">'c'</span><span class="special">,</span> <span class="char">'\r'</span><span
            class="special">,</span> <span class="char">'\n'</span><span class="special">,</span> <span
            class="char">'d'</span><span class="special">,</span> <span class="char">'e'</span><span
            class="special">,</span> <span class="special">...</span> <span class="special">}</span>
</pre>
    <p>
        The call to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span
            class="identifier">getline</span></code> then extracts the data up to
        and including the newline (which is discarded), so that the string <code class="computeroutput"><span
            class="identifier">line</span></code> contains:
    </p>
    <pre class="programlisting"><span class="special">{</span> <span class="char">'a'</span><span
            class="special">,</span> <span class="char">'b'</span><span class="special">,</span> <span class="special">...,</span> <span
            class="char">'c'</span><span class="special">,</span> <span class="char">'\r'</span> <span
            class="special">}</span>
</pre>
    <p>
        The remaining data is left in the buffer <code class="computeroutput"><span class="identifier">b</span></code>
        as follows:
    </p>
    <pre class="programlisting"><span class="special">{</span> <span class="char">'d'</span><span
            class="special">,</span> <span class="char">'e'</span><span class="special">,</span> <span class="special">...</span> <span
            class="special">}</span>
</pre>
    <p>
        This data may be the start of a new line, to be extracted by a subsequent
        <code class="computeroutput"><span class="identifier">read_until</span></code> operation.
    </p>
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